The present embodiments relate to a movable examination bed.
Emergency situations are often encountered during an examination made on an object to be examined using an examination bed. For instance, emergency situations such as, for example, power failure, having a patient's body part collide with or squeezed by diagnostic equipment, or a patient suddenly feeling discomfort may occur during the examination of patients using medical diagnostic equipment such as a Computed Tomographic (CT) machine. The medical diagnostic equipment may be turned off, and a movable platform of an examination bed may be manually and quickly pulled out, so as to quickly release the patient from the medical diagnostic equipment. When a previous operation needs to be continued after an emergency situation is over, the movable platform may be returned to the position where the movable platform was located before the occurrence of the emergency. With regard to a CT machine, two technical solutions may be adopted to solve the problems mentioned above.
The first technical solution is accomplished by installing an encoder on an examination bed. Currently, the available encoders include relative encoders and absolute encoders; relative encoders do not have a built-in power supply inside, so that when the CT machine is turned off, coordinate system data of the relative encoders no longer exist. Therefore, the relative encoders also require additional reference points to be set to be approximately re-positioned. The absolute encoders include a built-in power supply inside, so that when the CT machine is turned off, coordinate positions of the absolute encoders may still be recorded. Thus, the absolute encoders achieve high precision positioning, but costs are much higher than that of the relative encoders.
The second technical solution is accomplished by arranging a permanent magnet on a transport mechanism of an examination bed for a CT machine. Magnetic attraction may occur between the permanent magnet and a supporting body of the movable platform of the examination bed. The transport mechanism is operable to drive the movable platform such that the movable platform runs to the diagnostic region. When one of the emergency situations mentioned above occurs, the CT machine is turned off, the transport mechanism is separated from the movable platform by using an additionally arranged mechanical lever mechanism, and the movable platform is quickly pulled out. At this time, the positions of the transport mechanism and the permanent magnet thereon remain fixed. When the emergency situation is over, the movable platform is manually controlled until the supporting body is magnetically attracted onto the permanent magnet again. The movable platform is also returned to the position where the movable platform was located before the occurrence of the emergency situation.
In the second technical solution, two permanent magnets may be used. Therefore, the space occupied by the permanent magnets is large, and the costs are high. The permanent magnets also bring about some problems with transportation and installation, while the additional mechanical lever mechanism further increases the operation costs.